import time
incomplete_sign = 50 #.的数量
print('='*23+'开始下载'+'='*25)
for i in range(incomplete_sign + 1):
    completed = '*'*i #表示已完成
    incomplete = '.'*(incomplete_sign - i)#表示未完成
    percentage = (i/incomplete_sign)*100 # 百分比
    print('\r{:.0f}%[{}{}]'.format(percentage,completed,incomplete),end='')
    time.sleep(0.5)
print('\n'+'='*23+'下载完成'+'='*25)